Describe the bug

host.get_fact(TmpDir) simply returns empty on most environments. server.script operation fails due to this.

To Reproduce

• Operation code & usage

  # testtmpdir.py
  from pyinfra.context import host
  from pyinfra.facts.server import TmpDir
  
  print(host.get_fact(TmpDir))

  Run with pyinfra @local testtmpdir.py

• Target system information

Tested on two computers

1. Linux xxx 6.16.8-arch2-1 #1 SMP PREEMPT_DYNAMIC ... x86_64 GNU/Linux
2. Linux xxx 6.8.0-79-generic #79~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC ... x86_64 x86_64 x86_64 GNU/Linux

• Example using the @docker connector (helps isolate the problem)

  pyinfra @docker/ubuntu:22.04 testtmpdir.py

Expected behavior

I expect it to return /tmp from the fact, from what I understand from the docs

Meta

N/A

The bug is simply due to the TEMPDIR env variable not existing on most systems it seems.

https://github.com/pyinfra-dev/pyinfra/blob/3.x/src/pyinfra/facts/server.py#L60